For example, in an inspection step in a manufacturing process, a quality inspection is performed by using various sensors. By way of example, in an apparatus for detecting vibration, an acceleration sensor or the like is used, and an inspection of quality is performed based on detected vibration.
This kind of inspection apparatus includes a vibration detector, such as an acceleration sensor, which detects vibration generated by a product, a determination module which determines the presence/absence of abnormality, based on a detection result of the vibration detector, and a transmission line which transmits the detection result of the vibration detector to the determination module.
When abnormality is present in a product, for example, when a product including a rotary component has abnormality, the product generates abnormal vibration at a time of operation. If the vibration detector detects abnormal vibration, that is, if the vibration detector detects vibration which does not occur at a time of normal operation, the determination module determines that the product has abnormality.
On the other hand, when the vibration detector is faulty, even if the product generates abnormal vibration, the vibration detector cannot detect such vibration. Alternatively, when the transmission line is faulty, for example, when the transmission line is broken, the detection result of the vibration detector cannot be transmitted to the determination module. In this manner, even if the product generates abnormal vibration, if this abnormal vibration is not transmitted to the determination module, the determination module determines that the product is free of abnormality.